value unc_up unc_lo author ref method 17.47 0.120 0.120 Masiero 2014ApJ...791..121M NEATM 18.71 0.167 0.167 Masiero 2011ApJ...741...68M NEATM 20.49 2.000 2.000 Tedesco 2002AJ....123.1056T STM